Research project underway on the Rainy River

This is probably my least favourite time of year across Sunset Country.
I love ice fishing, but right now conditions are not ideal. We have a bunch of snow and slush on our lakes, the weather has not been great, and it’s generally the slowest fishing of the whole winter.
The days are starting to get longer and soon the sun will start to kick out some heat and start beating down the snow a little bit. Once this happens, the fishing seems to pick up for all species.
Looking farther ahead, it won’t be too long now until we can start thinking about open water. And for me and many others in the region, that first trip means getting the boat out on the Rainy River in late March or early April for some of the best walleye fishing in North America.
Over the past couple of years, I’ve had some great experiences on the Rainy and will make it an annual trip for many years to come.
Last summer, in a joint effort between the International Joint Commission (IJC), the Department of Fisheries and Oceans (DFO), the University of Waterloo Department of Biology, and the University of Waterloo Department of Civil and Environmental Engineering, a research project was launched on the Rainy River to study the possible effects of current discharge regulations from the International Falls dam (IFD) on the spawning and nursery habitat of lake sturgeon, walleye, and log perch.
The study is taking place on a 22-km stretch of the river from the dam downstream to the confluence of the Little Fork River.
Leading the charge on this project are two University of Waterloo students who spent the summer of 2012 in the Fort Frances area. Adrienne Smith and Jeff Muirhead, both Master’s of Science candidates at Waterloo, are working along with other agency employees and spending a bunch of time on the river.
I recently caught up with Muirhead to learn a little bit more about what they are doing. He explained that there currently is a regulation called the “2000 Rule Curve,” which mandates the operators of the dam at International Falls to maintain water levels in Rainy Lake within a certain range.
Flows in the Rainy River are an indirect result of the 2000 Rule Curve, which monitors and maintains water levels on Rainy Lake. The IJC has set an objective to re-evaluate their existing dam discharge practices in 2015.
The first part of the project involved characterizing the spawning and nursery habitat of the species of interest. They then evaluated the condition and age class structure of the target species, which gives them a good idea of the fish populations in the river.
Finally, the study aims to characterize and map the food web for each of these species.
Simultaneously with this data, they are characterizing hydraulics in the river—things like flow velocities in different depths and sections of the water column. Obviously, these current velocities change when water levels fluctuate, so they are trying to collect data over a wide range of dam discharges.
Field work is being performed during the 2012 and 2013 open-water seasons.
This information then will be used to look for trends and relationships between the fish, habitat, forage, and the physical processes that are occurring in the water column. The hope is that they then potentially can identify the dam discharges that are optimal for fish spawning processes.
During the 2012 field season, roughly 200 sturgeon and 300 walleye were caught, measured, tagged, and released, with the largest sturgeon coming in at around 110 pounds and the largest walleye at a little over nine pounds.
The best memory Muirhead has of his summer spent on the Rainy River was when he was out in his kayak collecting data when a large sturgeon breached the water about five feet away from him while he was paddling upstream.
Those of you that have been on the river before know how sturgeon like to do this. It’s just not very often it happens that close.
I will stay in touch with Muirhead and report his findings after the 2013 summer on the river.